Kiddie Tax: How a Child’s Investment Income Gets Taxed in 2025

The 2025 kiddie tax thresholds break a child’s unearned income into three layers, and each layer is taxed differently. The first $1,350 is tax-free, covered by the standard deduction for a dependent. The next $1,350 is taxed at the child’s own tax rate. Everything above $2,700 is the part actually subject to the kiddie tax, taxed at the parent’s marginal rate. Those figures are set out in the Instructions for Form 8615 and confirmed in IRS Topic 553, which states plainly that unearned income over $2,700 may be subject to the kiddie tax. Get these three numbers straight and the rest of the kiddie tax becomes far easier to reason about, because almost every calculation traces back to where a child’s income falls across those bands.

Start with the bottom layer. The dependent standard deduction for unearned income is $1,350 in 2025, so a child whose total unearned income is $1,350 or less owes zero federal tax and, in most cases, doesn’t even have to file. This is the band that makes small custodial accounts harmless. A kid with $900 of interest and dividends sails through with no return, no Form 8615, and no kiddie tax at all. The threshold is the reason a modest custodial account funded with a few thousand dollars often never generates a tax problem, because its annual income simply doesn’t reach the floor. That same floor is why grandparents who fund tiny accounts rarely create any paperwork for the family.

The middle layer runs from $1,350 to $2,700, another $1,350 band, and it’s taxed at the child’s own rate rather than the parent’s. For most kids that’s the 10% ordinary bracket, or potentially the 0% rate if the income is qualified dividends or long-term capital gains and the child’s total income is low enough. This layer is genuinely cheap, which is the point. Congress left a window where a child’s investment income still gets the child’s low rate, preserving a small benefit from gifting before the anti-abuse rule kicks in. So the first $2,700 of unearned income for 2025 is taxed lightly or not at all, split between the tax-free band and the child’s-rate band. Families who keep a child’s annual income just under $2,700 effectively pay no kiddie tax while still letting the assets sit in the child’s name.

The top layer is where the kiddie tax actually bites. Every dollar of unearned income above $2,700 is taxed at the parent’s marginal rate, which for a high-earning New York family can mean 32%, 35%, or 37% federally on ordinary income, or the 15% to 20% long-term capital gains rate if the income is qualified dividends or long-term gains. The character of the income carries up to the parent’s return: ordinary interest gets the parent’s ordinary rate, qualified dividends get the parent’s capital gains rate. This is why two children with identical $5,000 of unearned income can owe very different tax depending on whether the account held a high-yield bond fund or a qualified-dividend stock fund. The parent’s bracket, not the child’s, sets the price of that top slice.

Here’s a worked example tying the layers together. Suppose a 14-year-old has $4,000 of taxable interest in 2025 and no other income. The first $1,350 is tax-free. The next $1,350 is taxed at the child’s 10% rate, about $135. The remaining $1,300 (which is $4,000 minus $2,700) is the kiddie-tax layer, taxed at the parents’ rate; if they’re in the 24% bracket, that’s about $312. Total federal tax on the $4,000 is roughly $447, computed on Form 8615 and carried to the child’s Form 1040. Compare that to what the child alone would have paid at the 10% rate on the whole amount, and you can see the kiddie tax doing its job on that top slice. The difference, here a little over a hundred dollars, grows fast as the account and the parents’ bracket both climb.

A common mistake is assuming the thresholds adjust with the child’s age or the type of account. They don’t. The $1,350 and $2,700 figures for 2025 are the same whether the money sits in a UTMA, a custodial brokerage account, or a savings account in the child’s name, and whether the child is 6 or 16. The only age question is whether the kiddie tax applies at all, which is a separate test covered elsewhere. The dollar thresholds themselves are fixed for the year and indexed annually for inflation, so they tend to creep up a little each year. Another mistake is forgetting that capital gain distributions from a fund count toward the threshold, because they can push a child past $2,700 in a December no one was watching.

Looking ahead, the smart play is to check a child’s projected unearned income against the $2,700 ceiling before year-end, because that’s the line that separates a cheap return from an expensive one. If a custodial account is approaching the threshold, families have moves available, from the type of investment held to the timing of sales. Our tax strategy guides walk through several. The thresholds reset every January, so each tax year is its own puzzle, and the families who plan around the $2,700 line consistently pay less kiddie tax than those who find out about it after the 1099s arrive. Build the check into your December routine and the kiddie tax stops being a surprise and becomes just another number you manage, year after year, instead of a bill that lands every spring. It also helps to remember why the three-layer design exists in the first place: the tax-free band and the child’s-rate band together preserve a modest gifting benefit, while the parent’s-rate band shuts down the old strategy of parking a large dividend portfolio in a child’s name to escape a high bracket. Knowing the intent behind the kiddie tax makes the numbers easier to predict, because the rule behaves consistently once you see it as a graduated wall rather than a single cliff. A family that maps a child’s expected interest, dividends, and capital gain distributions against the $2,700 line each fall almost never gets surprised by the kiddie tax in April, and the few hundred dollars of planning attention routinely saves multiples of that at the parents’ top rate.

The kiddie tax applies to a child whose unearned income tops $2,700 in 2025 and who falls into one of three age categories: under 18 at year-end, exactly 18 with earned income that didn’t cover more than half their support, or a full-time student aged 19 through 23 in that same support situation. The age rule is the part that surprises families, because the kiddie tax can reach well into a child’s twenties when they’re still in college and living mostly on family money. The IRS Topic 553 spells out every condition that has to be met before Form 8615 kicks in, and missing any single one means the kiddie tax doesn’t apply at all. That stacked checklist is exactly why the rule is narrower in practice than its reputation suggests.

Take the conditions one at a time. First, the child’s unearned income has to exceed $2,700. Second, the child meets one of the three age tests above. Third, at least one of the child’s parents was alive at the end of the tax year, an odd-sounding rule that exists because the kiddie tax borrows the parent’s rate, so a living parent has to exist to supply that rate. Fourth, the child is required to file a return. Fifth, the child doesn’t file a joint return with a spouse. All five have to be true together. The kiddie tax is narrower than people assume precisely because of this stacked checklist, and any one failing condition takes the whole rule off the table for that year.

The under-18 category is the simplest. Any child under 18 at year-end with more than $2,700 of unearned income is subject to the kiddie tax, no support test required. This is the core group the rule was written for, the young kids whose parents or grandparents funded accounts in their names. There’s no escape valve here based on the child’s own earnings, because Congress assumed children this young aren’t supporting themselves. So a 12-year-old with a large custodial account is squarely covered regardless of any summer job, and even a child actor or young athlete with real wages still faces the kiddie tax on the investment side of their income.

The 18-and-student categories add the support test, and this is where the kiddie tax can be avoided. For an 18-year-old, or a full-time student aged 19 through 23, the kiddie tax applies only if the child’s own earned income was not more than half of their support. Flip that around: if the child earns enough to provide more than half their own support, the kiddie tax stops applying, even with a big investment year. A 20-year-old student working full time who genuinely covers most of their own living costs can fall out of the rule entirely. That’s a real, if demanding, planning lever for older kids approaching independence, and it rewards documenting who actually paid for what during the year.

Here’s a worked example. Marcus is 21 and a full-time college student. In 2025 he has $6,000 of dividend income from an account his parents funded, and he earned $8,000 from a part-time job. His total support for the year ran about $30,000, mostly paid by his parents through tuition, housing, and food. Because his $8,000 of earned income is far less than half of his $30,000 support, Marcus meets the age-and-support test and the kiddie tax applies. The unearned income above $2,700, which is $3,300, gets taxed at his parents’ marginal rate on Form 8615. Had Marcus earned $20,000 and paid more than half his own support, the kiddie tax would not have applied and that same $3,300 would be taxed at his own lower rate. The support math, not his age, is what decides it.

A frequent mistake is thinking the kiddie tax ends automatically at 18. It doesn’t. For students it can run through age 23, and the trigger that ends it is the support test, not a birthday. Parents of college students with custodial accounts are routinely caught off guard when the kiddie tax follows their “adult” child into junior year. Another mistake is forgetting the “parent alive” condition in the rare cases it matters, or assuming a child who files their own return is automatically outside the rule. Filing separately doesn’t dodge the kiddie tax; the child files Form 8615 on their own return and still borrows the parent’s rate for the top layer. The rule reaches the income wherever the child reports it.

Planning around the age rule means thinking ahead about when a child will genuinely cross into self-support. For families with significant custodial assets, the years between 18 and 24 are the window to watch, because that’s when the support test offers a way out that simply doesn’t exist for younger kids. If you have a college-age child with investment income and want to know whether the kiddie tax still applies to them, that’s exactly the kind of question we work through in an individual tax return engagement. The age each child ages out depends entirely on their own earnings and student status, so map it per child rather than assuming a single cutoff. Get the support math right for an older student and you can move their investment income back to their own low rate, which over a couple of college years adds up to real money the kiddie tax would otherwise have claimed. The practical discipline here is recordkeeping: write down who paid for tuition, rent, food, transportation, and the rest, because the support test turns on real dollars and the IRS expects the math to be defensible if it ever asks. A student who earns enough to cover more than half their own support has genuinely aged out of the kiddie tax, but a casual claim without numbers behind it won’t hold. For families with several children at different ages, the cleanest approach is to track each child separately every year, since one may be under 18 and squarely covered while another is a working college senior who has finally escaped the rule entirely.

Unearned income for the kiddie tax is any income that isn’t pay for work. That means taxable interest, ordinary and qualified dividends, capital gains, capital gain distributions from mutual funds, rents, royalties, taxable Social Security or pension income, and income distributed from a trust. Earned income, by contrast, is wages, salaries, tips, and net self-employment earnings, and none of it counts toward the kiddie tax. The line between the two decides the entire calculation, because only the unearned bucket is measured against the $2,700 threshold on Form 8615. Get the classification wrong and you either over-report and overpay, or miss a filing requirement entirely. The kiddie tax lives or dies on that single distinction.

The most common forms of unearned income for kids come from custodial accounts. A UTMA or custodial brokerage account holds investments in the child’s name, and whatever those investments pay out is unearned income to the child. Interest from bonds or a high-yield savings account is unearned. Dividends from stocks and funds are unearned. When the account sells an appreciated holding, the resulting capital gain is unearned. Even the December capital gain distributions that mutual funds make, often without the holder doing anything, are unearned income that can push a child over the threshold. Publication 929 details how each category flows through the kiddie-tax computation, and it treats all of these consistently as unearned regardless of where the money sits.

Earned income sits firmly outside the kiddie tax, and this is genuinely good news for working teenagers. A 16-year-old earning $7,000 at a part-time job owes no kiddie tax on any of those wages, because wages are earned. Better still, that earned income gets its own larger standard deduction on the child’s return, often sheltering it from tax entirely. So a hardworking teen with a job and no investments typically has a simple, low-tax return. The kiddie tax only enters the picture when investment income shows up, which is why the rule is really about gifted or inherited assets rather than a kid’s own labor. A child who funds a Roth IRA from those wages, by the way, is doing something the kiddie tax never touches.

The mixed case is where families need to pay attention, because many kids have both. Imagine a 17-year-old with $5,000 of wages from a summer job and $3,500 of dividends from a custodial account. The $5,000 of wages is earned income, taxed at the child’s rate with the earned-income standard deduction. The $3,500 of dividends is unearned, and since it exceeds $2,700, the portion above that threshold runs through the kiddie tax at the parents’ rate on Form 8615. The two streams are computed on separate tracks of the same Form 1040; they don’t pool together. Mislabeling the dividends as earned, or vice versa, throws off the whole return, and it’s a surprisingly common error on self-prepared returns.

Here’s a worked example that shows why the type of unearned income matters as much as the amount. Two children each have exactly $5,000 of unearned income in 2025, and their parents are both in the 24% bracket. Child A’s income is all ordinary interest from bonds. The $2,300 above the $2,700 threshold is taxed at the parents’ ordinary 24% rate, about $552. Child B’s income is all qualified dividends. That same $2,300 top layer is taxed at the parents’ long-term capital gains rate of 15%, about $345. Identical dollar amounts, a $200-plus difference in tax, driven entirely by the character of the unearned income. The character carries up from the child to the parent’s rate schedule, per the rules in Topic 553. Stretch that gap across many years and many thousands of dollars, and the holding choice quietly becomes one of the biggest levers a family controls. Run the same comparison for ten years of a growing account and the gap compounds: if both children’s accounts throw off $5,000 a year, Child A pays roughly $5,520 in kiddie tax over the decade while Child B pays about $3,450, a $2,000-plus difference created by nothing but the type of holding inside an otherwise identical account. Push the parents into the 35% bracket and Child A’s ordinary-interest tax balloons further while Child B’s qualified-dividend rate barely moves, widening the gap again. That’s the quiet power of income character, and it’s the single variable most families overlook when they fund a child’s account.

A common mistake is overlooking capital gain distributions, the surprise unearned income that mutual funds generate near year-end. A custodial account holding an actively managed fund can receive a sizable capital gain distribution in December even though nobody sold anything, and that distribution is unearned income that can blow through the $2,700 threshold unexpectedly. Another mistake is assuming money a grandparent gave the child is somehow earned because the child “has” it; the gift itself isn’t income, but everything the gifted money then earns is unearned income subject to the kiddie tax. The source of the principal doesn’t matter; what the principal produces does, and that’s the part families consistently underestimate.

Knowing what counts as unearned income lets you shape a custodial account to keep the kiddie tax small. Holdings that pay little current income and instead grow in value generate no unearned income until they’re sold, so a low-yield, buy-and-hold approach can keep a child’s reported unearned income under the threshold for years. Our guide on the taxable brokerage account digs into how different holdings throw off different amounts of taxable income. The takeaway is that the kiddie tax is partly within your control: by choosing what sits inside a child’s account, you influence how much unearned income shows up each year, and a thoughtfully built account can stay well under the line that triggers the parent’s rate. That control is the whole reason holding choice deserves as much attention as funding amount. One more category trips people up worth naming plainly: tax-exempt municipal bond interest is not subject to the kiddie tax for federal purposes, so a custodial account holding munis can generate income that stays outside the calculation entirely, though the yield trade-off rarely makes sense for a child in a low bracket. On the other end, taxable bond funds and high-turnover active funds are the worst offenders, layering ordinary interest and surprise capital gain distributions onto the unearned pile every year. If you remember one rule, make it this: classify every dollar a child receives as either earned or unearned before you do anything else, because that single sorting step determines whether the kiddie tax applies and how much it costs.

The choice between filing Form 8615 on your child’s own return and using the Form 8814 parent election comes down to a trade-off between convenience and total tax. Form 8615 means your child files their own Form 1040 and the kiddie tax is computed there. Form 8814 lets you skip the child’s return entirely by reporting their interest and dividends on your own return. The election is simpler, but it isn’t always cheaper, and treating it as automatic is one of the more common kiddie-tax mistakes we see. Both forms exist because Congress gave families a choice, and the right answer depends on your specific numbers rather than a rule of thumb.

Form 8814 comes with a strict eligibility checklist, all of which must be satisfied. The child’s gross income has to be under $13,500 for 2025. The income must be only interest and dividends, including capital gain distributions and Alaska Permanent Fund dividends, with nothing else in the mix. No estimated tax payments can have been made under the child’s name, and no prior-year overpayment can have been applied to the current year under the child’s Social Security number. There can be no backup withholding on the child’s income. And you have to be the parent qualified to make the election. The full list is in IRS Topic 553. Fail any condition, and Form 8814 is off the table, leaving Form 8615 on the child’s return as the path. Those conditions aren’t suggestions; one disqualifier voids the election.

The appeal of Form 8814 is obvious: one fewer tax return to prepare and file. For a busy family with a child who has a few thousand dollars of dividends and nothing complicated, folding it into the parents’ return saves time and a separate filing. But that convenience can cost real money, because the election adds the child’s income to the parents’ adjusted gross income. A higher AGI can push the parents into or further through the 3.8% net investment income tax, reduce or eliminate credits and deductions tied to income thresholds, and increase state tax, which often piggybacks on federal AGI. None of those ripple effects happen when the child files their own return, where the income stays on the child’s lower-AGI Form 1040. The hidden cost lives in those AGI-linked items, not in the kiddie tax line itself.

There’s also a quirk in how Form 8814 taxes the income that can either help or hurt. Under the election, the first chunk of the child’s income gets a small tax computed on Form 8814 itself, and the rest is added to the parents’ income. For some families this produces a result close to Form 8615; for others, especially higher earners with AGI-sensitive items, it produces a worse result. The only reliable way to know is to compute it both ways, which is exactly what a careful preparer does when the amounts are large enough to matter. We don’t guess; we run the comparison, because the two methods can diverge by hundreds or even thousands of dollars on the same income.

Here’s a worked example. The Patel family is in the 35% bracket and close to the net investment income tax threshold. Their 12-year-old has $8,000 of dividends in 2025. Using Form 8814, that $8,000 lands on the parents’ return, potentially dragging more of their own investment income into the 3.8% surtax and nudging AGI-based phaseouts. Filing the child’s own return with Form 8615 keeps the $8,000 on the child’s Form 1040; the kiddie tax still applies the parents’ rate to the layer above $2,700, but the income never inflates the parents’ AGI. For this family, the separate return with Form 8615 likely produces a lower combined bill, even though it’s more paperwork. For a family well below any threshold, Form 8814 might be the smarter, simpler choice. The right call genuinely flips depending on where the parents sit on the income ladder.

The common mistake is choosing Form 8814 purely to avoid filing a second return, without checking what it does to the parents’ AGI-driven items. That convenience can quietly cost more than the time it saves, particularly for high earners in a place like New York City where state and city tax both ride on federal AGI. Another mistake is missing a disqualifying condition, such as backup withholding or estimated payments under the child’s name, and electing 8814 when the child isn’t actually eligible. The eligibility rules aren’t optional, and the IRS can unwind an improper election. A third trap: assuming the election locks you in for future years, when in fact you choose anew each year based on that year’s numbers.

When the numbers are meaningful, the answer is to compute both methods and pick the lower total, which is the kind of analysis we build into an individual tax return engagement. Plan the election before filing season, because once you understand which path your family’s numbers favor, you can structure the child’s accounts to keep that path open, and the election decision becomes a deliberate choice rather than a default you stumble into. The families who treat it as a yearly comparison, not a set-and-forget habit, are the ones who consistently land on the cheaper side of the kiddie tax. There’s a quieter benefit to filing the child’s own return with Form 8615 that rarely gets mentioned: it builds a filing history in the child’s name, which can matter later for things like establishing residency, supporting a future Roth IRA based on earned income, or simply teaching a teenager what a tax return is. The Form 8814 election skips all of that by keeping everything on the parents’ return. Neither outcome is wrong, but it’s one more factor in a decision people treat as purely mechanical. When the dividend amounts are small and the family sits well below every income threshold, the election’s simplicity usually wins; when the amounts are large or the parents are near the surtax, the child’s own return with Form 8615 tends to be the cheaper kiddie-tax answer.

Planning around the kiddie tax starts with understanding that the tax only hits unearned income above $2,700, so the goal is to control how much taxable unearned income a child’s accounts generate each year. The main vehicles families use, custodial UTMA accounts, custodial brokerage accounts, and 529 college savings plans, each interact with the kiddie tax differently, and choosing among them is a real planning decision rather than a coin flip. The kiddie tax punishes income, not appreciation, which is the key insight that shapes every good strategy here. Build the accounts with that distinction in mind and you keep far more of the growth in the family instead of feeding it to the parents’ top bracket.

Custodial accounts, whether UTMA or a plain custodial brokerage account, are where the kiddie tax usually shows up, because they hold investments in the child’s name and whatever those investments pay out is the child’s unearned income. The planning lever is what you hold inside them. A custodial account full of high-yield bonds, dividend stocks, or actively managed funds throws off a steady stream of interest, dividends, and capital gain distributions every year, and that income piles up against the $2,700 threshold on Form 8615. The same account holding a low-yield, broad-market index fund that’s bought and held generates very little current income, because unrealized appreciation isn’t unearned income and isn’t taxed until you sell. So the single most effective custodial-account move is choosing tax-efficient, low-distribution holdings. Publication 929 confirms it’s the realized income, not the account balance, that drives the kiddie tax.

The 529 plan is the cleanest answer to the kiddie tax for education money, and it’s where a lot of custodial-account dollars probably should have gone in the first place. Inside a 529, investments grow with no annual tax on the dividends, interest, or gains, and withdrawals are completely federal-tax-free when used for qualified education expenses. Because there’s no annual taxable income, a 529 generates zero kiddie tax, year after year, no matter how large it grows. For families saving specifically for college, this sidesteps the entire kiddie-tax problem that a custodial brokerage account creates. The trade-off is flexibility: 529 money is meant for education, and non-qualified withdrawals face tax and a penalty on the earnings, so it’s not the right home for money the child might need for something else. New York residents also get a state tax deduction for contributions to New York’s 529, which sweetens the deal for families here, as detailed by New York State.

Timing of sales is another lever inside custodial accounts. Because capital gains are realized only when you sell, you control when that unearned income shows up. Spreading the sale of an appreciated holding across two or more tax years can keep each year’s realized gain under the $2,700 threshold, so the kiddie tax never touches it. The same logic applies to harvesting losses inside the account to offset gains, keeping net realized income low. This is hands-on planning, but for a sizable custodial account it can save meaningful tax over the years a child holds the account, and it pairs naturally with the asset-location thinking in our tax strategy guides. A little intentional timing each December often does more than any single investment pick.

Here’s a worked example that ties the strategies together. The Reyes family wants to save $50,000 for their 8-year-old. Option one: a custodial UTMA holding a dividend-focused fund yielding 3%. That’s $1,500 of dividends a year now, growing as the account grows, eventually crossing $2,700 and triggering the kiddie tax at the parents’ 32% rate. Option two: put the education portion in a 529 holding the same growth investments. The 529 generates zero annual taxable income and zero kiddie tax, the New York contribution may earn a state deduction, and qualified withdrawals come out tax-free. Over a decade, option two can save several thousand dollars in kiddie tax alone, before counting the tax-free growth and the state deduction. The catch is that the 529 money is committed to education, which is fine if that’s the goal but limiting if the child’s path changes.

The common mistake is defaulting to a custodial UTMA for all of a child’s savings because it’s easy to open, without thinking about the kiddie tax it will eventually generate or the fact that UTMA money becomes the child’s outright at the age of majority, with no strings on how they spend it. A 529 keeps the parent in control and dodges the kiddie tax for education dollars; a custodial brokerage account offers flexibility but invites the kiddie tax and hands over control later. Neither is universally right. The smart approach matches the vehicle to the purpose: 529 for college money, a thoughtfully invested custodial account for flexible money you’re willing to let the child control eventually, and an eye on the $2,700 threshold every year. Splitting savings across both vehicles, rather than forcing one to do everything, is usually the cleaner answer.

If you want a plan built around your kids, your savings goals, and your bracket, that’s the work our tax strategy consulting team does. Decide the structure early, because the families who pick the right vehicle when a child is young pay almost no kiddie tax over eighteen years, while those who improvise with a high-yield custodial account end up feeding the parents’ top bracket every spring. The earlier you align the account with its purpose, the more of the growth stays in the family instead of going to the kiddie tax, and the less you’ll spend untangling a tax-clumsy account later when the balances, and the stakes, are far larger. It’s worth saying that the kiddie tax shouldn’t scare a family out of saving for a child at all; a few hundred dollars of tax on a growing account is a good problem, and the rule only ever touches the income above $2,700, never the principal or the unrealized growth. The mistake isn’t saving too much for a kid, it’s saving in the wrong wrapper and letting a high-yield, high-turnover holding generate income the family didn’t need to realize. Match the vehicle to the goal, keep an eye on the threshold each year, and the kiddie tax becomes a manageable line item rather than an annual shock. For most families that simply means a 529 for the college money and a tax-efficient index fund for anything else held in the child’s name.